Classification for esophagogastric junction (EGJ) complex based on physiology

Abstract

We propose a new classification for esophagogastric junction (EGJ) incorporating both physiologic and morphologic characteristics. Additionally, we contrast it with the Chicago v 3.0 EGJ classification. With Institutional Review Board (IRB) approval, prospectively maintained database was queried to identify patients who underwent high-resolution manometry (HRM) and pH-study between October 2011 and October 2015. Patients with prior foregut intervention, pH study on acid suppression, esophageal dysmotility, or lower esophageal sphincter-crural diaphragm separation of >5 cm were excluded. We classified patients into three groups-Type-A: Complete overlap of lower esophageal sphincter-crural diaphragm (single high-pressure zone); Type-B: Double high-pressure zone with pressure inversion point (PIP) at or above lower esophageal sphincter; Type-C: Double high-pressure zone with PIP below lower esophageal sphincter. A total of 214 included patients were divided into Type-A (n = 101), Type-B (n = 32), and Type-C (n = 81). Abdominal lower esophageal sphincter length (AL), lower esophageal sphincter pressure (LESP), and lower esophageal sphincter pressure integral (LESPI) were significantly lower in Type-C than both Type-A and Type-B [AL(cm): 0.2 vs. 2(P < 0.001) vs. 1.6(P <0.001); LESP(mmHg): 20.1 vs. 32.1(P < 0.001) vs. 29.2(P < 0.001); LESPI(mmHg.cm.s): 187 vs. 412(P < 0.001) vs. 343(P < 0.05)] while overall lower esophageal sphincter length(OL) and Integrated Relaxation Pressure (IRP) were significantly lower in Type-C than Type-A [OL(cm): 2.9 vs. 3.6(P < 0.001); IRP(mmHg): 8.2 vs. 9.6(P < 0.05)]. Type-C patients had significantly higher positive pH score (>14.7) than Type-A and Type-B [72% vs. 47% (P < 0.05) vs. 41% (P < 0.001)]. In Type-C morphology, there is both anatomical and physiological deterioration, weakest lower esophageal sphincter function (abdominal length, lower esophageal sphincter pressure, and lower esophageal sphincter pressure integral) and is most likely to be associated with pathological reflux. This proposed classification incorporates both physiological and morphological derangements in a graded fashion.

Esophageal motility disorders on high‐resolution manometry: Chicago classification version 4.0©

“…LES‐CD separation should be scored as the distance between the center of the CD and LES signal during inspiration, unless obscured in which case the LES position should be scored at expiration (Strong Recommendation). The EGJ complex should be defined based on LES‐CD separation and location of the RIP. (Low GRADE, Conditional Recommendation) 86–92 …”

“…• The EGJ complex should be defined based on LES-CD separation and location of the RIP. (Low GRADE, Conditional Recommendation) [86][87][88][89][90][91][92] As for EGJ morphology, it was acknowledged that there were three subtypes: 1) normal with the CD superimposed on the LES and the RIP localizing proximal to the complex; 2) LES-CD separation with the RIP localized proximal to the CD; and 3) LES-CD separation with the RIP localized proximal to the LES. However, there was no consensus regarding the subtype classification scheme (I, II, III vs A, C, B) and both versions were deemed acceptable ( Figure S4).…”

“…However, there was no consensus regarding the subtype classification scheme (I, II, III vs A, C, B) and both versions were deemed acceptable ( Figure S4). 86,91 More research is clearly needed applying standardized, pre-specified methodology. The EGJ Metrics technical review details further recommendations regarding measurement of the EGJ complex in setting of hiatal hernia and temporal variability, as well as intragastric pressure and the role of end-expiratory LES pressure.…”

Esophageal physiology—an overview of esophageal disorders from a pathophysiological point of view

“…17 A recent study argued that the location of the respiratory inversion point (and the resulting length of the intraabdominal LES) was the most important factor in determining the clinical significance of the HH. 66 This study noted that with respiratory inversion point at or above the level of the LES, the LES is functionally in the abdomen (even in the setting of a hernia) and is reinforced by intraabdominal pressure (Fig. 3).…”

“…For these individuals, correction of the hernia is a necessary step in any antireflux procedure. 66 The gastroesophageal flap valve is another anatomic structure of the EGJ complex that plays an important role in establishing the antireflux barrier. 40 The flap valve is a 180-degree muscu-lomucosal fold visualized by retroflexion during upper endoscopy and is graded from I to IV based on how closely this fold is apposed to the endoscope.…”